Herbicidal and phytohormonal amidoximes

ABSTRACT

Amidoximes of the formula ##STR1## are disclosed. R represents a hydrogen atom or a hydrogen, lower alkyl (C 1  -C 4 ) or phenyl; R 1  represents lower alkyl or a metal atom and Ar represents substituted or unsubstituted phenyl or a five-membered substituted or unsubstituted aromatic heterocyclic group where the hetero atom is selected from the group O, S and N. The compounds have phytohormonal activity at low dosages in plants and herbicidal activity at higher levels.

This is a divisional of application Ser. No. 722,215, filed Sept. 10,1976, now U.S. Pat. No. 4,116,974.

The present invention relates to new derivatives of amidoximes of thegeneral formula: ##STR2## their preparation, the compositions in whichthey are present, and the treatments carried out with thesecompositions.

In the general formula (I), R represents a hydrogen atom or an alkylgroup containing 1 to 4 carbon atoms, or a phenyl group.

R₁ represents a hydrogen atom or an alkyl group containing 1 to 4 carbonatoms, or a metal atom, and

Ar represents a phenyl group substituted by 1 to 3 substituents whichmay be identical or different and are chosen from among halogen atomsand the following groups: alkyl containing 1 to 4 carbon atoms,hydroxyl, alkoxy of which the alkyl part contains 1 to 4 carbon atoms,alkylthio of which the alkyl part contains 1 to 4 carbon atoms,alkylsulphinyl of which the alkyl part contains 1 to 4 carbon atoms,alkylsulphonyl of which the alkyl part contains 1 to 4 carbon atoms,trifluoromethyl, trifluoromethyl, trifluoromethylthio, carboxyl,alkoxycarbonyl of which the alkyl part contains 1 to 4 carbon atoms,nitro, amino, alkylamino of which the alkyl part contains 1 to 4 carbonatoms, dialkylamino of which each alkyl part contains 1 to 4 carbonatoms, acylamino of which the acyl part contains 1 to 4 carbon atoms,alkoxycarbonylamino of which the alkyl part contains 1 to 4 carbonatoms, azido, alkanoyl containing 1 to 4 carbon atoms, sulphamoyloptionally substituted at the nitrogen by one or two alkyl groups, inwhich case each alkyl part contains 1 to 4 carbon atoms, or phenyl, orAr represents an aromatic heterocyclic group with 5 chain members whichcontains an atom or oxygen, sulphur or nitrogen as the hetero-atom andis optionally substituted by a halogen atom, an alkyl group containing 1to 4 carbon atoms, an alkoxy group of which the alkyl part contains 1 to4 carbon atoms, an alkylthio group of which the alkyl part contains 1 to4 carbon atoms or a phenylalkyl group of which the alkyl part contains 1to 4 carbon atoms and is itself optionally substituted.

According to the invention, the products of the general formula (I) canbe obtained in accordance with one of the following methods:

(1) By the action of a product of the general formula: ##STR3## in whichR and R₁ are defined as above and Y represents a halogen atom, on anamidoxime of the general formula: ##STR4## in which Ar is defined asabove.

The reaction is generally carried out in an aqueous-organic solvent suchas a mixture of ethanol and water or dimethylformamide and water, in thepresence of an alkaline condensation agent such as sodium hydroxide,potassium hydroxide or a tetraalkylammonium hydroxide, and at atemperature of between 20° and 80° C.

The products of the general formula (III) can be obtained by the actionof hydroxylamine on a nitrile of the general formula:

    Ar--CN                                                     (IV)

in which Ar is defined as above.

The reaction is generally carried out in an organic solvent such asaqueous ethanol, at a temperature of between 20° and 80° C.

(2) By the action of a product of the general formula: ##STR5## in whichR and R₁ are defined as above, on an imino-ether salt of the generalformula: ##STR6## in which Ar is defined as above and HA represents amolecule of hydrochloric acid (HCl) or of fluoboric acid (HBF₄).

The reaction is generally carried out in a basic organic solvent such aspyridine, at a temperature of about 20° C.

The salt of an imino-ether, of the general formula (VI), can be obtainedeither by the action of a solution of hydrogen chloride in ethanol on anitrile of the general formula (IV), or by the action of triethyloxoniumfluoroborate (Meerwein salt) on a amide of the general formula:

    Ar--CONH.sub.2

in which Ar is defined as above.

(3) By the action of a compound of the formula: ##STR7## on a compoundof the formula R₁ OH (IX), where Ar, R and R₁ have the same definitionas in the formula (I).

The reaction is carried out by heating the compound VIII at atemperature of the order of 60° C. in the presence of the alcohol (IX)and then evaporating the alcohol under reduced pressure.

The products of the general formula (I), in which R₁ represents ahydrogen atom, can be obtained by saponification of a product of thegeneral formula (I), in which R₁ represents an alkyl group containing 1to 4 carbon atoms.

The reaction is generally carried out in an organic solvent such asmethanol or ethanol in the presence of a base such as sodium hydroxideor potassium hydroxide, at a temperature of about 20° C.

The products of the general formula (I) for which Ar represents a phenylgroup substituted by one or more alkylsulphinyl groups can be obtainedfrom the compounds of the general formula (I), for which Ar represents aphenyl group substituted by one or more alkylthio groups, by oxidationof the alkylthio group or groups to alkylsulphinyl groups. The oxidationcan be carried out at ordinary temperature by dissolving the compound tobe oxidized in acetone and adding a 30% strength (weight/volume)hydrogen peroxide solution to the above solution.

The products according to the present invention exhibit remarkableproperties which render them particularly useful in the agriculturalfield.

If they are used at doses of between 1 and 100 g/hl of water, theyexhibit particularly valuable phytohormonal properties. In that case,they possess auxinic actions analogous to those of indolylacetic acid orof derivatives of the phenoxyacetic acids. They are essentially usefulin assiting the setting of fruit on certain plants (tomatoes),preventing the shedding of leaves or fruit or increasing the formationof roots.

If they are used at doses of between 0.5 and 10 kg/ha, the productsaccording to the invention exhibit herbicidal properties, in particularagainst dicotyledon plants, both in pre-emergence and in post-emergence.

For use in practice, the compounds according to the invention are rarelyemployed by themselves, but instead are employed in the form ofagricultural compositions which also form the subject of the presentapplication.

The compositions generally comprise, in addition to the active materialaccording to the invention, a carrier and/or a surface-active agentwhich are compatible with the active material and can be used inagriculture. In these compositions, the content of active product can bebetween 0.005 and 95% by weight.

The term "carrier" in the sense of the present description denotes anorganic or inorganic, natural or synthetic material, with which theactive material is associated in order to facilitate its application tothe plant, to the seed or to the soil, or its transport, or itshandling. The carrier can be solid (clays, natural or syntheticsilicates, resins, waxes, solid fertilizers and the like) or fluid(water, alcohols, ketones, petroleum fractions, chlorinated hydrocarbonsor liquified gases).

The surface-active agent can be an emulsifier, a dispersing agent orwetting agent and each of these can be ionic or non-ionic. By way ofexample there may be mentioned the salts of polyacrylic acids and ofligninsulphonic acids, and condensates of ethylene oxide with fattyalcohols, fatty acids or fatty amines.

The composition according to the invention can be prepared in the formof wettable powders, dusting powders, granule solutions, emulsifiableconcentrates, emulsions, suspensions, suspension concentrates andaerosols.

The wettable powders are usually prepared in such a way that theycontain from 20 to 95% by weight of active material, and they usuallycontain, in addition to a solid carrier, from 0 to 5% of wetting agent,from 3 to 10% by weight of a dispersing agent and, where necessary, from0 to 10% by weight of one or more stabilizers and/or other additives,such as penetrating agents, adhesives or anti-caking agents, dyestuffsand the like.

By way of example, the composition of a wettable powder is given below,the precentages being expressed by weight:

    ______________________________________                                        Active material (compound of the formula I)                                                              50%                                                Calcium lignosulphate (deflocculating agent)                                                             5%                                                 Isopropylnaphthalenesulphonate (wetting agent)                                                           1%                                                 Silica anti-caking agent   5%                                                 Kaolin filler              39%                                                ______________________________________                                    

The powders for dusting are usually prepared in the form of a dustconcentrate having a composition similar to that of a wettable powder,but without dispersing agent, and are diluted, at the use site, with asupplementary amount of a solid carrier so that a composition whichusually contains from 0.5 to 10% by weight of active material isobtained.

The emulsifiable concentrates which can be applied by spraying usuallycontain, in addition to the solvent and, where necessary, a co-solvent,from 10 to 50% by weight/volume of active material, from 2 to 20% byweight/volume of emulsifiers and from 0 to 20% by weight/volume ofappropriate additives, such as stabilizers, penetrating agents,corrosion inhibitors, dyestuffs and adhesives.

By way of example, the composition of an emulsifiable concentrate isgiven below, the amounts being expressed in g/l:

    ______________________________________                                        Active material (compound of the formula I)                                                             400 g/l                                             Dodecylbenzenesulphonate   24 g/l                                             Nonylphenol oxyethylated with 10 molecules of                                 ethyleneoxide              16 g/l                                             Cyclohexanone             200 g/l                                             Aromatic solvent          q.s.p. 1 liter.                                     ______________________________________                                    

The suspension concentrates, which can also be applied by spraying, areprepared so that a stable fluid product which does not sediment isobtained, and they usually contain from 10 to 75% by weight of activematerial, from 0.5 to 15% by weight of surface-active agents, from 0.1to 10% by weight of anti-sedimentation agents such as protectivecolloids and thixotropic agents, from 0 to 10% by weight of appropriateadditives, such as anti-foam agents, corrosion inhibitors, stabilizers,penetrating agents and adhesives and, as the carrier, water or anorganic liquid in which the active material is substantially insoluble;certain organic solid materials or inorganic salts can be dissolved inthe carrier to assist in preventing the sedimentation or to act asantifreeze agents for the water.

Aqueous dispersions and emulsions, for example compositions obtained bydiluting a wettable powder or an emulsifiable concentrate according tothe invention with water, also fall within the general scope of thepresent invention. These emulsions can be of the water-in-oil type or ofthe oil-in-water type and can have a thick consistency such that of a"mayonnaise".

For a so-called "ultra-low volume" application, entailing spraying asvery fine droplets, solutions, in organic solvents, which contain from70 to 95% of active material are prepared.

The compositions according to the invention can contain otheringredients, for example protective colloids, adhesives or thickeners,thixotropic agents, stabilizers or sequestering agents as well as otherknown active materials having pesticidal properties, in particularinsecticides or fungicides.

The examples which follow are given, without implying a limitation, inorder to illustrate the invention.

EXAMPLE 1 Preparation ofO-ethoxycarbonyl-methyl-thiophene-2-carboxyamidoxime

The process used is the second of the processes mentioned in the presentapplication. A mixture of ethyl thiophene-2-carboximidate hydrochloride(140 g.) and ethyl amino-oxyacetate hydrochloride (104 g.) in pyridine(2,350 cc.) is stirred at a temperature of about 20° C. for one hour.The pyridine is evaporated under reduced pressure (2 mm Hg) at atemperature of about 30° C., the residue is then taken up in ethylacetate (one liter), and the pyridine hydrochloride formed is filteredoff and washed with ethyl acetate (2×500 cc.). The filtrate is washedwith water (a total of 500 cc), decanted, dried over sodium sulphate anddecolorized with animal charcoal. After filtration, and evaporation ofthe solvent at 30° C. under reduced pressure (20 mm Hg), a limpid oil isobtained, which crystallizes when triturated in isopropyl ether (100cc.). After isolation by filtration, and dryingO-ethoxycarbonyl-methylthiophene-2-carboxamidoxime (150.7 g.), meltingat 58° C., is obtained. After recrystallization from isopropyl ether(3.3 parts), the pure product, which is in the form of white crystals,melts at 62° C.

EXAMPLES 2 TO 45

On following the same process as in Example 1, with suitable startingmaterials, the following products of Table I are obtained.

                                      TABLE I                                     __________________________________________________________________________     ##STR8##                                                                     __________________________________________________________________________                               Melting                                                                       point (°C.)                                                            after re-                                          Ex.                        crystal-                                                                            Other charac-                                No.                                                                              Ar             R R.sub.1                                                                          Yield                                                                             lization                                                                            teristics                                    __________________________________________________________________________        ##STR9##      H C.sub.2 H.sub.5                                                                  73% 131                                                3                                                                                 ##STR10##     H C.sub.2 H.sub.5                                                                  100%                                                                              59                                                 4                                                                                 ##STR11##     H C.sub.2 H.sub.5                                                                  91% 112                                                5                                                                                 ##STR12##     H C.sub.2 H.sub.5                                                                  75% 70                                                 6                                                                                 ##STR13##     H C.sub.2 H.sub.5                                                                  92% 130                                                7                                                                                 ##STR14##     H C.sub.2 H.sub.5                                                                  59% 67-68                                              8                                                                                 ##STR15##     H C.sub.2 H.sub.5                                                                  92% 49                                                 9                                                                                 ##STR16##     H C.sub.2 H.sub.5                                                                  73% 39.5                                               10                                                                                ##STR17##     H C.sub.2 H.sub.5                                                                  84% 97                                                 11                                                                                ##STR18##     H C.sub.2 H.sub.5                                                                  100%                                                                              109                                                12                                                                                ##STR19##     H C.sub.2 H.sub.5                                                                  100%                                                                              53                                                 13                                                                                ##STR20##     H C.sub.2 H.sub.5                                                                  89% 75                                                 14                                                                                ##STR21##     H C.sub.2 H.sub.5                                                                  96% 87                                                 15                                                                                ##STR22##     H C.sub.2 H.sub.5                                                                  94%       Boils at 175° C./0.2 mm Hg.           16                                                                                ##STR23##     H C.sub.2 H.sub.5                                                                  97% 95                                                 17                                                                                ##STR24##     H C.sub.2 H.sub.5                                                                  75% 90                                                 18                                                                                ##STR25##     H C.sub.2 H.sub. 5                                                                 100%                                                                              66                                                 19                                                                                ##STR26##     H C.sub.2 H.sub.5                                                                  100%      Boils at 155° C./0.5 mm Hg.           20                                                                                ##STR27##     H C.sub.2 H.sub.5                                                                  97% 163                                                21                                                                                ##STR28##     H C.sub.2 H.sub.5                                                                  93% 91                                                 22                                                                                ##STR29##     H C.sub.2 H.sub.5                                                                  87% 74                                                 23                                                                                ##STR30##     H C.sub.2 H.sub.5                                                                  80% 100                                                24                                                                                ##STR31##     H C.sub.2 H.sub.5                                                                  99%       Boils at 142-148° C./ 0.4 mm Hg       25                                                                                ##STR32##     H C.sub.2 H.sub.5                                                                  95% 80                                                 26                                                                                ##STR33##     H C.sub.2 H.sub.5                                                                  92% 82                                                 27                                                                                ##STR34##     H C.sub.2 H.sub.5                                                                  71% 141                                                28                                                                                ##STR35##     H C.sub.2 H.sub.5                                                                  98% 146                                                29                                                                                ##STR36##     H C.sub.2 H.sub.5                                                                  91% 124                                                30                                                                                ##STR37##     H C.sub.2 H.sub.5                                                                  63%       Chromato- graphed oil n.sub.D.sup.25 =                                        1.5655                                       31                                                                                ##STR38##     H C.sub.2 H.sub.5                                                                  91% 98                                                 32                                                                                ##STR39##     H C.sub.2 H.sub.5                                                                  84% 112                                                33                                                                                ##STR40##     H C.sub.2 H.sub.5                                                                  98% 65                                                 34                                                                                ##STR41##     H C.sub.2 H.sub.5                                                                  88% 118                                                35                                                                                ##STR42##     H C.sub.2 H.sub.5                                                                  82%  --   Oil converted to the oxalate boils at                                         149° C.                               36                                                                                ##STR43##     H C.sub.2 H.sub.5                                                                  94%  --   Boils at 10°/ 0.2 mm Hg               37                                                                                ##STR44##     H C.sub.2 H.sub.5                                                                  98% 114                                                38                                                                                ##STR45##     H Na     186                                                39                                                                                ##STR46##     H Na     214                                                __________________________________________________________________________                                   Melting point                                                                 (°C.) or                                Examples                                                                            AR        R    R.sub.1                                                                            Yield                                                                              characteristics                                __________________________________________________________________________    40                                                                                   ##STR47##                                                                              H    C.sub.2 H.sub.5                                                                    49%  Boils at 178° C./ 0.4 mm Hg oil         41                                                                                   ##STR48##                                                                              H    C.sub.2 H.sub.5                                                                    75%  56° C.                                  42                                                                                   ##STR49##                                                                              CH.sub.3                                                                           C.sub.2 H.sub.5                                                                    98%  Oil                                            43                                                                                   ##STR50##                                                                              H    C.sub.2 H.sub.5                                                                    99%  110° C.                                 44                                                                                   ##STR51##                                                                              H    C.sub.2 H.sub.5                                                                    65%  60° C. (Hemihydrate)                    45                                                                                   ##STR52##                                                                              H    C.sub.2 H.sub.5                                                                    66%  121° (C.)                               __________________________________________________________________________

EXAMPLE 46 Preparation of the sodium saltof-O-(carboxymethyl)thiophene-2-carboxamidoxime.

The process used for this example is the first of the processesdescribed in the present application.

A suspension obtained from bromoacetic acid (29.4 g.) and 0.99 Nethanolic sodium hydroxide solution (213 cc.) is added over the courseof 5 minutes to a mixture of thiophene-2-carboxamidoxime (30 g.) and an0.99 N ethanolic sodium hydroxide solution (213 cc.), and the batch isstirred for 16 hours. The ethanol is evaporated under reduced pressure(20 mm Hg) at a temperature of between 20° C. and 30° C. The crystalsobtained are taken up in ethyl acetate (210 cc.), filtered off, washedwith ether (2×100 cc.) and dried at a temperature of about 20° C. underreduced pressure (20 mm Hg). The white crystals thus obtained aredissolved in water (390 cc.) and sodium chloride (40 g.) is added,followed, after solution is complete, by the addition of citric acid (15g.). The precipitate which forms is filtered off and washed and dried.O-Carboxymethylthiophene-2-carboxamidoxime (15.65 g.) melting at 130° C.is thus obtained. On again saturating the mother liquors with sodiumchloride and following the above procedure, a second crop ofO-carboxymethylthiophene-2-carboxamidoxime, also melting at 130° C., isobtained. After recrystallization from water, the pure product melts at131° C.

EXAMPLE 47

A mixture of α-bromobutyric acid (16.7 g.) and an 0.97 N ethanolic NaOHsolution (103 cc.) is added to the suspension obtained fromthiophene-2-carboxamidoxime (14.2 g.) and an 0.97 N ethanolic sodiumhydroxide solution (103 cc.) Following the method described in Example48, the sodium salt of O-(1-carboxypropyl)-thiophene-2-carboxamidoxime(14.1 g.), melting at 246° C., is obtained.

EXAMPLE 48

Preparation of the compounds according to the formula I, with R₁ ═H, bysaponification of the compounds for which R₁ ═an alkyl group.

An 0.1 N sodium hydroxide solution (1,250 cc.) is added to a solution ofO-ethoxycarbonylmethyl-thiophene-2-carboxamidoxime (22.8 g.) in ethanol(220 cc.). The suspension thus formed is stirred for 40 hours at atemperature of about 20° C. The solution obtained is clarified byfiltration over Supercel and neutralized by adding a normal hydrochloricacid solution (125 cc.). The mixture is concentrated to 2/3 of itsvolume under reduced pressure at a temperature of about 50° C. and isthen extracted with methylene chloride (a total of 1,100 cc.). Theorganic extracts are dried over calcined magnesium sulphate anddecolorized by means of decolorizing charcoal. After filtration, andevaporation of the solvent under reduced pressure (20 mm Hg),O-carboxymethyl-thiophene-2-carboxamidoxime (7 g.) melting at 120° C. isobtained. A second extraction of the mother liquors with ethyl acetate(a total of 750 cc.), followed by a treatment as above, gives a furtheramount of product (9.1 g.) melting at 129° C.

After recrystallization from water,O-carboxymethylthiophene-2-carboxamidoxime melts at 131° C. Thiscompound has already been described in Example 46 of the presentapplication, where it is obtained in accordance with a differentprocess.

EXAMPLE 49 Preparation ofO-butoxycarbonylmethyl-thiophene-2-carboxamidoxime.

The process used for this example is the third of the processesdescribed in the present application.

A mixture of O-chloroformylmethyl-thiophene-2-carboxamidoximehydrochloride (13 g.) and n-butanol (65 cc.) is heated at 60° C. for 4hours. The alcohol is evaporated at a temperature of about 40° C. underreduced pressure (20 mm Hg) the residue is then taken up in a solutionof sodium bicarbonate (7.7 g.) in water (130 cc.), and the organicsubstance is extracted with ethyl acetate (3×130 cc.). The organicextracts are washed with water (2×50 cc.) and dried over sodiumsulphate. After filtering, and evaporating the solvent under reducedpressure (20 mm Hg) at a temperature of about 40° C.,O-butoxycarbonylmethylthiophene-2-carboxamidoxime (13 g.) is obtained inthe form of an oil. After dissolution in cyclohexane (100 cc.), theproduct crystallizes. It is filtered off and dried at a temperature ofabout 25° C. under reduced pressure (1 mm Hg).O-Butoxycarbonylmethyl-thiophene-2-carboxamidoxime (12.3 g.) melting at31° C. is thus obtained.

EXAMPLE 50

Following the procedure of the preceding example and starting fromO-chloroformylmethyl-thiophene-2-carboxamidoxime hydrochloride (15. g.)and methanol (100 cc),O-methoxycarbonylmethyl-thiophene-2-carboxamidoxime (10.7 g.) melting at82° C., is obtained.

EXAMPLE 51

This example describes the preparation ofO-ethoxycarbonylmethyl-3-methylsulphinyl-benzamidoxime, from thecompound described in Example 13, by oxidation of the methylthiosubstituent, attached to the phenyl group, to give a methylsulphinylsubstituent.

A 30% strength (weight/volume) solution of hydrogen peroxide (2.1 cc.)is added to a solution ofO-ethoxycarbonylmethyl-3-methylthio-benzamidoxime (5.03 g.) in acetone(100 cc.), and the mixture is left to stand for 7 days. The solvents areevaporated at a temperature of about 30° C. under reduced pressure (20mm Hg) and the residue is then taken up with methylene chloride (50 cc.)and water (20 cc.). The organic phase is decanted and dried over sodiumsulphate. After filtration, and evaporation of the solvent, an oil (5g.) is obtained, which is chromatographed on a column containing silica(50 g.). Elution with methylene chloride gives unreactedO-ethoxycarbonylmethyl-3-methylthio-benzamidoxime (0.9 g.), followed byO-ethoxycarbonylmethyl-3-methylsulphinylbenzamidoxime (3.5 g.) meltingat 58° C. After recrystalization from a mixture of isopropyl ether (25cc.) and ethanol (5 cc.), the pure product melts at 90° C.

EXAMPLE 52

A condensation product (10 parts) of ethylene oxide and octylphenol inthe ratio of 10 molecules of ethylene oxide per molecule of octylphenolis added to a solution ofO-ethoxycarbonylmethyl-thiophene-2-carboxamidoxime (25 parts) in amixture (65 parts) of equal parts of toluene and acetophenone. Thesolution is used, after dilution with water, at the rate of 100 cc. ofthis solution per 100 liters of water.

The phytohormonal activity of the products of the present applicationcan be demonstrated in the following tests:

(1) Setting of fruit of tomatoes

1 drop (0.05 cc.) of the solution or suspension of the product to bestudied is deposited on the ovary of emasculated flowers of tomatoplants. After a period of observation of 5 days, the percentage of fruitformed relative to the comparison is noted.

Used in this way, at a concentration of 10 mg/liter, the product ofExample 1 shows a degree of setting of fruit of 100%, relative to thecomparison (0%). The fruit formed is devoid of pips.

(2) Propagation of tomato leaves

The 3rd and 4th leaves are taken from tomato stems (Marmande variety)having 5 to 6 leaves. The petiole of each leaf is dipped, over a lengthof 2 to 3 cm, into the solution to be studied, contained in a test tube.8 days after starting the experiment, the number of roots formed on thepetioles of the treated leaves is counted and measured.

Used in this way, at a concentration of 1 mg/liter, the product ofExample 1 causes the formation of 100% of rooted leaves, while theformation is zero in the case of the petioles of the comparison plants.

(3) Shedding of leaves

The experiment is carried out on Coleus. Cuttings formed by a fragmentof stem carrying two petioles are dipped in the solution of the productto be studied. The separation of the petiole from the stem is followedas a function of time.

With the comparison plants, the separation is complete after two days.

With the product of Example 3, used at a concentration of 100 mg/liter,no separation whatsoever is observed after one week after starting theexperiment.

The herbicidal activity of the products of the general formula (I) canbe demonstrated in the following manner:

Seeds of various species, namely wheat (Triticum sativum), lentil (Lensculinaris), radishes (Raphanus sativus), sugar beet (Beta vulgaris) andslender foxtail (Alopecurus agrestis) are sown in plastic pots (180 cc.capacity), containing, to a height of 6 cm, a mixture composed of 1/3 ofclean earth, 1/3 of vegetable mould and 1/3 of river sand, at the rateof about 30 seeds per pot. For each concentration of product, two potsof wheat and four pots of the other species are used.

For the purpose of a post-emergence treatment, the sowing is carried outin a greenhouse one week before the start of the experiment, so that thesmall plants are at the following stage at the time of treatment:

    ______________________________________                                        wheat and foxtail:                                                                           3 leaves                                                       lentil:        3 leaves                                                       beet and radish:                                                                             2 well-developed cotyleden                                                    leaves.                                                        ______________________________________                                    

The treatment is carried out by spraying the solution or suspension ofthe product, the pots being placed on a pot-turner. Each pot is given 1cc. of the solution. The doses of the product to be studied are 1 and 8kg/ha.

During pre-emergence testing, the seeded surface of the pots is allowedto dry whereupon it is covered by about 1 cm with the same earthmixture. The pots are watered by spraying twice a day. During postemergence testing the treated seedlings are allowed to dry. The earthmixture is then moistened by placing the base of the pots in a dishcontaining water.

Three weeks after the start of the treatment, the number of plants ineach pot is counted, and their height is measured.

The results are expressed in percentages relative to the comparisonplants.

The results are summarized in the table which follows:

                                      TABLE II                                    __________________________________________________________________________           Dose of                                                                Product of                                                                           Product in                                                                          PRE - EMERGENCE     POST - EMERGENCE                             Example No.                                                                          kg/ha Wheat                                                                             Lentil                                                                            Radish                                                                            Beets                                                                             Foxtail                                                                           Wheat                                                                             Lentil                                                                            Radish                                                                            Beets                                                                             Foxtails                     __________________________________________________________________________    I      I     20  100 75  100 75  0   100  30 50  25                                  10    20  100 100 100 85  20  100  60 70  50                           3      I     0   20  0   60  50  0   0    10 30  0                                    8    0   100 40  90  90  0   40   60 80  20                           5      I     0   100 75  0   30  0   60   70 50  0                                   10    0   100 100 100 50  0   100  100                                                                              100 0                            7      I     0   20  0   50  50  0   0    0  0   0                                   10    20  60  0   70  50  0   0    0  0   0                            8      I     0   30  0   0   0   0   0    0  0   0                                   10    0   100 100 100 50  0   100  0  25  0                            9      I     0   0   0   0   0   0   0    0  0   0                                   10    0   25  0   100 75  0   0    0  0   0                            12     I     0   0   0   0   0   0   40   60 0   0                                   10    0   100 0   0   50  0   100  100                                                                              50  0                            38     I     20  100 0   0   70  0   60   0  50  0                                   10    70  100 100 100 100 0   100  40 100 20                           39     I     10  100 0   50  75  0   50   0  25  50                                  10    20  100 100 75  80  30  100  25 25  75                           41     I     0   100 50  80  75  0   60   60 25  25                                  10    50  100 100 100 90  0   100  60 50  50                           43     I     0   100 0   0   50  0   0    0  0   0                                   10    30  100 100 100 75  0   60   0  0   0                            44     I     0   100 40  0   50  0   75   0  0   0                                   10    20  100 90  100 80  0   100  80 50  20                           46     I     20  100 80  80  75  20  100  40 20  20                                  10    60  100 100 100 95  20  100  100                                                                              100 80                           47     I     0   100 0   75  50  0   40   0  0   40                                  10    0   100 60  100 75  0   50   20 50  40                           __________________________________________________________________________

What is claimed:
 1. A new amidoxime of the formula ##STR53## in which Rrepresents a hydrogen atom or an alkyl group containing 1 to 4 carbonatoms, or a phenyl group,R₁ represents a hydrogen atom or an alkyl groupcontaining 1 to 4 carbon atoms, or a metal atom, and Ar represents a 5membered aromatic heterocyclic group which contains an atom of oxygen asthe hetero-atom and is optionally substituted by a halogen atom, analkyl group containing 1-4 carbon atoms, an alkoxy group, an alkylthiogroup or a phenylalkyl group, wherein the alkyl moiety of each of saidgroups contains 1 to 4 carbon atoms.
 2. The compound according to claim1, of the formula: ##STR54## in which R represents a hydrogen atom or analkyl group of 1-4 carbon atoms,R₁ represents a hydrogen atom, an alkylgroup of 1-4 carbon atoms or a metal atom, and Ar represents a fivemembered aromatic heterocyclic group which contains an oxygen atom asthe hetero-atom and is optionally substituted by a halogen atom, amethyl group, a methoxy group, a methylthio group or a phenylalkylgroup.
 3. The amidoxime according to claim 1 in which Ar is the furylgroup.
 4. The amidoxime according to claim 2 in which Ar is the furylgroup.
 5. The amidoxime according to claim 1 of the formula: ##STR55##wherein R₁ is as defined in claim
 1. 6. A phytohormonal and herbicidalcomposition for plants containing, as the active material, at least onecompound according to claim 1 in phytohormonal or herbicidally effectiveamount, in association with a carrier and/or a surface-active agentcompatible with the said compound and suitable for agricultural use. 7.The composition according to claim 6, wherein the content of said activematerial is between 0.005 and 95% by weight.
 8. A process for thetreatment of plants, wherein said composition according to claim 6 isapplied to the plants or their environs.
 9. The process of treatmentaccording to claim 8, wherein the dose of active material applied pertreated hectare is between 0.5 and 10 kg/ha.